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13.2. Querying Example

The following provides an example of how to set up and run a query in Red Hat JBoss Data Grid.

In this example, the Person object has been annotated using the following:

Example 13.4. Annotating the Person Object

@Indexed
public class Person implements Serializable {
    @Field(store = Store.YES)
    private String name;
    @Field
    private String description;
    @Field(store = Store.YES)
    private int age;
}

@Indexed
public class Person implements Serializable {
    @Field(store = Store.YES)
    private String name;
    @Field
    private String description;
    @Field(store = Store.YES)
    private int age;
}

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Assuming several of these Person objects have been stored in JBoss DataGrid, they can be searched using querying. The following code creates a SearchManager and QueryBuilder instance:

Example 13.5. Creating the SearchManager and QueryBuilder

SearchManager manager =	Search.getSearchManager(cache);
QueryBuilder builder = manager.buildQueryBuilderForClass(Person.class) .get();
Query luceneQuery = builder.keyword()
    .onField("name")
    .matching("FirstName")
    .createQuery();

SearchManager manager =	Search.getSearchManager(cache);
QueryBuilder builder = manager.buildQueryBuilderForClass(Person.class) .get();
Query luceneQuery = builder.keyword()
    .onField("name")
    .matching("FirstName")
    .createQuery();

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The SearchManager and QueryBuilder are used to construct a Lucene query. The Lucene query is then passed to the SearchManager to obtain a CacheQuery instance:

Example 13.6. Running the Query

CacheQuery query = manager.getQuery(luceneQuery);
List<Object> results = query.list();
for (Object result : results) {
    System.out.println("Found " + result);
}

CacheQuery query = manager.getQuery(luceneQuery);
List<Object> results = query.list();
for (Object result : results) {
    System.out.println("Found " + result);
}

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This CacheQuery instance contains the results of the query, and can be used to produce a list or it can be used for repeat queries.

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13.2. Querying Example

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